At what temp does an engine catch on fire

[Curlychump]

Everyone probably knows this by now but i don't, i am making a boat that turns itself off is the temp is to high, if someone could please reply quickly it would be great.

[Pete]

it is supposed to start having problems at 100 degrees I have heard, though I dont know how hot it needs to get to catch fire.

I have always made a simple thermostat that turns the coolant pump on when it reaches 70 degrees.

Honestly it is very hard to make an engine overheat. I have freqently done designs with radiators in inaccessible positions, even with no coolant pump, and it just doesnt seem to matter. For boats, just sucking seawater in works fine too.

[Teamkiller]

120 is a critical temp.

It is actualy very easy to overheat - just set RPS limit to maximum and give a full throttle without load. 1 radiator or even outer whater is not enough to handle this.

[Pete]

I've never bothered increasing the rev limiter. The engines just run out of torque and make no additional power. They all perform best at about half the standard rev limit.

What I want to know, is if there are any effects from running an engine too cold. You would expect greater fuel consumption, but I can't say ive noticed anything. Might make a rig and test that actually.

[Curlychump]

Thankyou everyone

[Arc]

Originally posted by Pete:

I've never bothered increasing the rev limiter. The engines just run out of torque and make no additional power. They all perform best at about half the standard rev limit.

Rev is good if you are driving low load 1:1, say like a rotor pulling something lightweight. But yea, no point in land/water based vehicles to max it out, gearboxes will be much better for this.

[Pete]

Basically, if you mouse over a running engine, those percentages it gives you tell you how well it is running. Anything less than 100%, it needs more flow to achieve the power output for that rpm.
So to a certain extent, adding more exhausts, adding bigger or more air inlets, will help you rev an engine more and actually get something out of it. But there is still a limit to what you can get out of it.

I havnt needed to increase the rev limiter even in diesel helicopters. High revs drink fuel no matter what you do.

[NoriXa]

After 1.0 update the temps where changed i had to change my automatic generator to 110 Degree Hard Stop bc at 115 it starts fire (small engine) medium and large engine start fire at 120.

[Popeye]

I've been trying to get my karhsten 3x3 i6's to catch on fire for about 15 minutes now so I could test the sprinkler system. I even blocked the water inlets and am running them at 50 rps each. It's taking forever lol

[Ra-Ra-Rasputin]

Originally posted by man53n:

I've been trying to get my karhsten 3x3 i6's to catch on fire for about 15 minutes now so I could test the sprinkler system. I even blocked the water inlets and am running them at 50 rps each. It's taking forever lol

Not sure why you're replying to a 2 year old thread.

If you're looking to overheat your engines, running them at 50 RPS for less than a minute is a plenty, unless you've cheated the parts so that they don't overheat or have overheating disabled.

[Curlychump]

im still looking at this post lol

[murphyc123]

Originally posted by Pete:

it is supposed to start having problems at 100 degrees I have heard, though I dont know how hot it needs to get to catch fire.

I have always made a simple thermostat that turns the coolant pump on when it reaches 70 degrees.

Honestly it is very hard to make an engine overheat. I have freqently done designs with radiators in inaccessible positions, even with no coolant pump, and it just doesnt seem to matter. For boats, just sucking seawater in works fine too.

Maybe it was fine in July 2021, but in July 2023 DO NOT use seawater without desalinating it first. Using seawater will decrease the performance of your cooling after a short while.

[GrumpyOldMan]

Originally posted by murphyc123:

Maybe it was fine in July 2021, but in July 2023 DO NOT use seawater without desalinating it first. Using seawater will decrease the performance of your cooling after a short while.

Direct seawater cooling is the most efficient way to keep an engine cool, nothing else even comes close.

The coolant scaling (salt scale buildup in the pipes) only happens if the coolant manifold goes above 100° and is a slow buildup over time. It's not an issue.

[Curlychump]

Originally posted by murphyc123:

Originally posted by Pete:

it is supposed to start having problems at 100 degrees I have heard, though I dont know how hot it needs to get to catch fire.

I have always made a simple thermostat that turns the coolant pump on when it reaches 70 degrees.

Honestly it is very hard to make an engine overheat. I have freqently done designs with radiators in inaccessible positions, even with no coolant pump, and it just doesnt seem to matter. For boats, just sucking seawater in works fine too.

Maybe it was fine in July 2021, but in July 2023 DO NOT use seawater without desalinating it first. Using seawater will decrease the performance of your cooling after a short while.

Thanks mate

[Booze_Rooster]

Can verify. Using seawater cooled modular 3x3s. Keep the temp under 100 and it's fine

[GrumpyOldMan]

Originally posted by Goose:

i have cooling systems that can keep an engine running at 13 RPS around-under like 40C

On my recent 11m interceptor boat I'm running 2 16cyl 1x1 supercharged at 42 rps and 120kts continuously without overheating, with just a single coolant manifold using sea water, it doesn't climb above ~65-70°.

If I were to use radiators, I'd have to use 3x3 due to space constraints and even then, a single one most likely wouldn't cut it.

Just to put it into perspective, heh.